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arXiv · 2106.06270

Measurement of onset of structural relaxation in melt-quenched phase change materials

Benedikt Kersting·Syed Ghazi Sarwat·Manuel Le Gallo·Kevin Brew·Sebastian Walfort·Nicole Saulnier·Martin Salinga·Abu Sebastian
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Abstract

Chalcogenide phase change materials enable non-volatile, low-latency storage-class memory. They are also being explored for new forms of computing such as neuromorphic and in-memory computing. A key challenge, however, is the temporal drift in the electrical resistance of the amorphous states that encode data. Drift, caused by the spontaneous structural relaxation of the newly recreated melt-quenched amorphous phase, has consistently been observed to have a logarithmic dependence in time. Here, we show that this observation is valid only in a certain observable timescale. Using threshold-switching voltage as the measured variable, based on temperature-dependent and short timescale electrical characterization, we experimentally measure the onset of drift. This additional feature of the structural relaxation dynamics serves as a new benchmark to appraise the different classical models to explain drift.

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Benedikt Kersting, Syed Ghazi Sarwat, Manuel Le Gallo, Kevin Brew, Sebastian Walfort, Nicole Saulnier, Martin Salinga, Abu Sebastian. 2021-06-11. Measurement of onset of structural relaxation in melt-quenched phase change materials. https://arxiv.org/abs/2106.06270

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